CVE-2019-1365

What is this vulnerability?

CVE-2019-1365 is categorized as a critical security flaw with a CVSS base score of 9.9. Based on our vulnerability intelligence, this issue occurs when the application fails to securely handle untrusted data boundaries.

An elevation of privilege vulnerability exists when Microsoft IIS Server fails to check the length of a buffer prior to copying memory to it.An attacker who successfully exploited this vulnerability can allow an unprivileged function ran by the user to execute code in the context of NT AUTHORITY\system escaping the Sandbox.The security update addresses the vulnerability by correcting how Microsoft IIS Server sanitizes web requests., aka 'Microsoft IIS Server Elevation of Privilege Vulnerability'.

This architectural defect enables adversaries to bypass intended security controls, directly manipulating the application's execution state or data layer. Immediate strategic intervention is required.

Risk Assessment

Impact on Systems

✅ Data Exfiltration: Attackers can extract sensitive data from backend databases, configuration files, or internal services.

✅ Authentication Bypass: Exploiting this flaw may allow unauthorized access to protected resources and administrative interfaces.

✅ Lateral Movement: Once initial access is gained, attackers can pivot to internal systems and escalate privileges.

How to Fix and Mitigate CVE-2019-1365

1. Apply Vendor Patches: Upgrade affected components to their latest, non-vulnerable versions immediately.
2. Implement Input Validation: Ensure all user-supplied data is validated, sanitized, and type-checked before processing.
3. Deploy Runtime Protection: Use Precogs continuous monitoring to detect exploitation attempts in real time.
4. Audit Dependencies: Review and update all third-party libraries and transitive dependencies.

Defending with Precogs AI

Microsoft IIS Server contains an elevation of privilege vulnerability due to a buffer overflow. Attackers send crafted HTTP requests that trigger a memory copy operation without proper length validation, executing arbitrary code with elevated privileges. Precogs Binary SAST uncovers missing bounds checks during network request processing.

Use Precogs to continuously scan your codebase, binaries, APIs, and infrastructure for this vulnerability class and related attack patterns. Our AI-powered detection engine combines static analysis with threat intelligence to identify exploitable weaknesses before attackers do.

Start scanning with Precogs →

Vulnerability Code Signature

Attack Data Flow

Vulnerable Code Pattern

# ❌ VULNERABLE: Unsanitized Input Flow
def process_request(request):
    user_input = request.GET.get('data')
    # Taint sink: processing untrusted data
    execute_logic(user_input)
    return {"status": "success"}

Secure Code Pattern

# ✅ SECURE: Input Validation & Sanitization
def process_request(request):
    user_input = request.GET.get('data')
    
    # Sanitized boundary check
    if not is_valid_format(user_input):
        raise ValueError("Invalid input format")
        
    sanitized_data = sanitize(user_input)
    execute_logic(sanitized_data)
    return {"status": "success"}

How Precogs Detects This

Precogs AI Analysis Engine maps untrusted input directly to execution sinks to catch complex application security vulnerabilities.\n